Explained my process for reaching a solution: 1) information gathering (dimensions of the golf balls, dimensions of the interiour of the bus, any other constraints, etc.) 2) propose a solution using the information on hand, 3) discuss collaboratively with panel about possible complications or unforeseen issues, 4) offer alternative suggestion based on panel's feedback or guidance. Ultimately, they want you to demonstrate that you can actively work toward solving a problem in a collaborative manner.